9 replies to this topic

[SelfTransformingMachineElf]

I couldn't decide where to put this post - it's mostly a general sterilization question about PCing bag spawn.  I remember reading recently that bag spawn has to be sterilized for considerably longer than jar spawn.  I'm assuming you've just got to have considerably more water than usual?

 

I'm also a little concerned about the gas required to PC bags for hours on the stove.  I'm thinking about creating a solar collector and heating up the PC that way.  I've seen some pictures - seems slick.  So this is pretty related to the other thread I just posted about a solar oven for pasteurization.

 

Maybe the right answer is to get the biggest AA PC I can find ( I guess that's the 941 - 41 qts) and running an outdoor burner.  With the help of the sun, probably wouldn't require a lot of gas.

 

Sure would like to have an actual autoclave - has anyone ever priced them?  Are they even buyable as general population?

[kcmoxtractor]

To keep your PC from running out of water tape a couple quarters to the weight. It can go 6-8 hours with 2 quarters taped to the weight, depending on where the pressure settles.

Actual full sized autoclaves need your local or state code engineer to sign off before you can run them. Some places it's for any pressure boiler, sometimes it's only for boilers that do 15+psi. The whole system usually costs 50-100k, depending on size. The boiler cost and installation is the most expensive part, since it has to be done by a licensed plumber.

You should check out low pressure sterilization methods. You can sterilize a LOT of substrate for cheap using atmospheric steam temperature.

If you use supplements in the bags then you only need 1 or 2 cups of grain to inoculate each bag. A single 5 lb grain bag inoculates 12-25 substrates at that spawn ratio.

A 23 quart presto cooker will hold 4x 5lb bags, so you're looking at 50-100 subs each PC run. It's really easy to maximize your effort and output using supplemented substrate.

Edited by kcmoxtractor, 02 May 2021 - 08:35 PM.

[TVCasualty]

 

I'm also a little concerned about the gas required to PC bags for hours on the stove.  I'm thinking about creating a solar collector and heating up the PC that way.  I've seen some pictures - seems slick.  So this is pretty related to the other thread I just posted about a solar oven for pasteurization.

 

Once your PC is up to pressure it doesn't take much gas to keep it there.

 

There's really no way around using a lot of energy to heat a given amount of mass up to that temp and hold there for that long.

 

Solar thermal tech can be used to pre-heat the water you put in the PC (or can even generate dry steam) but it's probably not going to be worth the trouble and expense, frankly. And no one has developed a reliable solar sterilization or pasteurization method (e.g., a large solar collector/concentrator for heating a retort or bulk pasteurizer) because they can't be made reliable enough for commercial use (thanks to those damn clouds, and Winter) and there's not enough of a non-commercial market to justify manufacturing them.

 

I'd love nothing more than to stop using fossil fuels altogether, but until they are no more they can't be beat for reliability and efficiency. And when they are no more then we're not going to be growing fungi since we'll have other much more pressing priorities.

[SelfTransformingMachineElf]

Thanks for the numbers, kcmo.  I've got some sclerotia formers I'm interested in using bags for, so I can set them back for a few months.  So using as spawn is out - these are direct substrate bags.  The quarter trick is interesting indeed - good idea!  I think eventually I'll just get the AA 941, then as TV says, once it gets up to pressure it won't take quite so much energy to keep it there.  AA is all sold out of the 941 right now.  I heard last year there was a canning boom what with Covid and all.  Hopefully I can get my hands on one some time this year.

 

I suppose you want to make sure the bags don't touch the sides of the PC, huh?

[TVCasualty]

 

I suppose you want to make sure the bags don't touch the sides of the PC, huh?

 

That can be avoided by lining the cooker with a wet towel before putting them in.

 

I found stainless steel cook pots that fit almost exactly into my 941's (I had to bend the handles to make them fit). They're useful for simmering/prepping grain if you do that and then later they work as liner pots that allow you to take all your spawn bags out at once (it's a lot easier to carry than the whole damn cooker!). The liner pot also keeps the bags off the sides so there's no melting, and your bags aren't sitting in the water needed to run the cooker. So I use the pots instead of towels.

Edited by TVCasualty, 03 May 2021 - 11:19 AM.

[kcmoxtractor]

Thanks for the numbers, kcmo. I've got some sclerotia formers I'm interested in using bags for, so I can set them back for a few months. So using as spawn is out - these are direct substrate bags. The quarter trick is interesting indeed - good idea! I think eventually I'll just get the AA 941, then as TV says, once it gets up to pressure it won't take quite so much energy to keep it there. AA is all sold out of the 941 right now. I heard last year there was a canning boom what with Covid and all. Hopefully I can get my hands on one some time this year.

I suppose you want to make sure the bags don't touch the sides of the PC, huh?

No problem at all!

TBH, I think AA PCs are overrated. Their 41 quart autoclaves are good, but the weight on their PCs can't be adjusted like a Presto. So their PCs can't really be run at 15 psi with bags, gotta run at 12 or 13 psi IME. Supply issues with All American are pretty common, it's not just during COVID.

The bags may be able to touch the sides, depending on your elevation. Gotta be above 5,500 feet elevation or use a wet towel.

[SelfTransformingMachineElf]

I do like that 41 qt though.  Something to be said for the brutal efficiency of it!

[kcmoxtractor]

One more thing about the 941c, it weighs 33 lbs.

So 6 bags of grain is 30 lbs, the canner is 33 lbs, plus the water and towel, which is another ~20 lbs.

Total of about 83 lbs when full.

[TVCasualty]

TBH, I think AA PCs are overrated. Their 41 quart autoclaves are good, but the weight on their PCs can't be adjusted like a Presto.

 

Wait, I thought that the upgrade only cost fifty cents?

 

 

 

 

To keep your PC from running out of water tape a couple quarters to the weight.

 

 

[Just ignore me I got rained out and started drinking early]

Edited by TVCasualty, 04 May 2021 - 04:13 PM.

[Juthro]

I agree with KC's point that a 23qt presto, or the 21qt AA921 being a better, and a more economical choice for most people.  The AA941 is a monster, and is (IMO) overkill unless your going to be running some serious material all the time.   That, and I appreciate the ability to run the canner inside year round, as opposed to needing to run it on a banjo burner outside.

 

As far as my experience with my AA921, I've been using it hard for over 12 years, and it has never even gotten close to running dry. 

 

As a disclaimer, I don't do bagged spawn, but I have canned countless cases of salmon, and that has to cycle for 120 min for half pints & pints, or 160 min for quarts. (10psi for 1000' or less, 15psi for anything higher in altitude)

Edited by Juthro, 04 May 2021 - 06:35 PM.